Looking at the title, I guessed what this was about.
Finding a decent dentist is fucking hard. I travel 40 minutes to my dentist because he's solid and I don't want to switch if I don't have to.
You want someone who is going to identify problems and correct them, but not try and make everything a problem. Basically, look at where they spend their money and listen to what they recommend.
You don't want a dirty office, but you also don't need crown molding and gold leaf to fill a cavity.
I had a wisdom tooth issue and went to a dentist. He extracted it, said I had a number of cavities, etc. Never scheduled a follow up with him. Went to a different dentist, he said I had considerable plaque, but couldn't really tell on the cavities until he cleaned that up. So I did that and then he said I only had one or two.
They recommended I get a Sonicare. While they sold them, they also said I could get them anywhere, but to make sure I get one as it would help with plaque.
My current dentist had to extract one of my teeth because my wisdom tooth cracked it. He had also wanted to remove the wisdom tooth because the gap could be problematic, but after extracting the cracked tooth, he had to tap out. He told me that my roots are apparently the longest he's ever seen. So unless an actual problem develops, he was going to leave the wisdom tooth. And if I ever need another extraction, he was going to refer me to a surgeon. Other than that, it's just been cleanings and checkups.
So yeah, you really need to vet your dentist. If a dentist ever tells you you have multiple cavities, get a second opinion. Drilling a hole in a tooth and filling it with epoxy is quick and nets them a couple hundred per hole.